1. Field of Invention
The present invention relates to a composition, material layer and method for forming the same used in field effect transistor (FET). More particularly, the present invention relates to a composition and a dielectric layer formed by the same and method for forming the dielectric layer.
2. Description of Related Art
For the semiconductor carrier transmission of the field effect transistor, a voltage is applied to the gate, and sufficient induced charges are formed at the interface between the semiconductor and the gate dielectric layer so as to promote the carrier transmission. In order to that the FET has a high current ID in low voltage operation, capacitance is also involved in addition to the carrier mobility and the channel length between the source and drain electrodes. The thinner the thickness of the film of the dielectric layer is and the higher the dielectric constant is, and the higher the capacitance is.
3M company provides a dielectric layer with high dielectric constant in U.S. Pat. No. 6,586,791, wherein the gate dielectric layer is formed by coating the suspended solution formed by mixing the nanometer ceramic powder into polymer material. However, stripes may be formed on the surface of the dielectric layer made by the method, and therefore, the roughness of the surface is worse, so that leakage path is easily formed to generate a high leakage current.